1. Field of the Invention
The present invention is directed to interfacing a calculator keyboard with an external computer processor, and also interfacing a calculator with an external computer processor so that the keypads and the processor of the calculator operate independently by the control of the external computer processor.
2. Description of the Related Art
One example of the many calculator programs is a Windows.RTM. type of software program which provides a calculator program for a DOS operating system of a personal computer. However, such calculator programs are not widely used and in particular, the Windows.RTM. type of calculator program is not widely used because a mouse driven operator interface is used which requires the operator to physically move the mouse across the screen to the image of the key that they wish to depress and then click the mouse button to register the key depression.
Although the keyboard of the personal computer could be used to input some of the calculator keys, some of the keys critical to business operations such as MEMORY +, MEMORY -, MEMORY TOTAL, MEMORY SUBTOTAL, MEMORY CLEAR, CLEAR ENTRY, TOTAL, SUBTOTAL, BACKSPACE, GRAND TOTAL, PERCENT, PERCENT+, PERCENT-, EQUAL, EQUALS+, EQUALS-, NON ADD, CHANGE SIGN (+/-), .0..0., .0..0..0., CONSTANT, ITEM COUNT, SQUARE, SQUARE ROOT, PERCENT INCREASE AND PERCENT DECREASE keys, for example, are not included on PC keyboards. Therefore, the Windows.RTM. type of calculator program provides the display of some additional keys on the screen of the personal computer for access by the mouse. Furthermore, other feature keys such as ADD MODE, CONSTANTS and ITEM COUNT are missing from the screen of the Windows.RTM. type of calculator program. In addition, existing keys such as BACKSPACE, MULTIPLY and DIVIDE are provided on the screen of the Windows.RTM. Calculator Program such that they are either totally out of touch position or they are not labeled in a recognizable form.
Another known program similar to the Windows.RTM. type of calculator program is a Nortons Utilities type of program which has a screen based calculator program imbedded within its many applications. Even though this program has a paper tape audit trail for making corrections, a mouse is still mandatory for many operations and the operator is required to continually jump back and forth between the keyboard and the mouse to activate key images on the screen that do not have actual equivalent keys on the keyboard. Another conventional program is a Sidekick type of program which operates as a terminate and stay resident program. The Sidekick type of program has the same operating difficulties as in the other PC screen based programs along with a lack of features for business users.
Presently, even though many types of keyboards have been connected to a personal computer, a calculator type keyboard has not been interfaced with a personal computer so that the personal computer can be used for number processing the entries from the calculator type keyboard. Furthermore, the keyboard of calculators do not have auto repeat on all keys, in contrast to personal computer keyboards, which have auto repeat on all keys and thereby causes double entries. Also, calculator keyboards have manual function repeat (keys must be released before the next key is accepted) in contrast to personal computers where operational functions will repeat automatically or manually if the key is held too long and calculator keyboards take advantage of key rollover features without causing double entries from automatic repeat (on PC keyboards) which increases the accuracy when using a calculator keyboard.
In a calculator keyboard, function keys are within easy reach of the ten key section. In contrast, on personal computers, function keys are arranged similar to a typewriter at various positions on the keyboard or certain function keys are required to be operated by a mouse causing two-handed PC calculator operation which causes a failure of the operator to maintain hand position on the input document as a guide to the next input line and constant hand movement between the keyboard and the mouse. Therefore, the present invention is directed to interfacing a calculator keyboard and a calculator with a personal computer which increases the number processing capabilities by reducing eye, hand and arm movement.
In addition, there are several known types of keypads which may be connected to a personal computer for providing an additional keypad layout. However, the additional keypad layout may not necessarily provide additional calculator functions. For example, a generic number pad such as the Launching Pad by Genovation, Inc. provides a keypad for portable computers. However, the Launching Pad and other generic number pads do not provide additional calculator functions as such generic number pads only provide some calculator conventional key functions already provided on standard personal computer keyboards without providing additional calculator functions. Also, a separate keyboard calculator is known such as a keyboard calculator having keypads similar to the keys provided on the Key pro FX 9000 by Focus Electronic Co., Ltd. for example. However, only the standard keypad functions are sent for processing by the personal computer and the additional calculator functions provided on the Key pro type of keypad are not processed and sent to the personal computer. Furthermore, an on-line keypad, such as an ABACUS type of keypad by Key Tronic for example, is known which can do a one time sending of a calculated result when connected to a personal computer. However, the ABACUS type of line keypad cannot send calculator functions to the personal computer which are not already provided on the personal computer.